Squeaking from distributor. Do I need to replace the whole distributor assembly? And what could cause this?

Hi, My car recently started making a squeaking noise. My car was parked for about 10 days in the garage without being started. The noise is very similar to a loose or worn drive belt. I checked the belts first all 3 are ok. The sound is definitely coming from the distributor. I pulled the cap and rotor and there is allot of rust inside. I replaced whole distributor aprox 2.5 years ago (I don't remember the mileage, sorry) I did not replace the wires at the same time. Is the distributor toast again? And could this be caused by high resistance in the wires, or just a bad quality distributor?